Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
awilliam
GitHub Repository: awilliam/linux-vfio
 Path: blob/master/arch/sh/kernel/io.c
10817 views
1
/*

2
 * arch/sh/kernel/io.c - Machine independent I/O functions.

3
 *

4
 * Copyright (C) 2000 - 2009  Stuart Menefy

5
 * Copyright (C) 2005  Paul Mundt

6
 *

7
 * This file is subject to the terms and conditions of the GNU General Public

8
 * License.  See the file "COPYING" in the main directory of this archive

9
 * for more details.

10
 */

11
#include <linux/module.h>

12
#include <linux/pci.h>

13
#include <asm/machvec.h>

14
#include <asm/io.h>

15


16
/*

17
 * Copy data from IO memory space to "real" memory space.

18
 */

19
void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)

20
{

21
	/*

22
	 * Would it be worthwhile doing byte and long transfers first

23
	 * to try and get aligned?

24
	 */

25
#ifdef CONFIG_CPU_SH4

26
	if ((count >= 0x20) &&

27
	     (((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {

28
		int tmp2, tmp3, tmp4, tmp5, tmp6;

29


30
		__asm__ __volatile__(

31
			"1:			\n\t"

32
			"mov.l	@%7+, r0	\n\t"

33
			"mov.l	@%7+, %2	\n\t"

34
			"movca.l r0, @%0	\n\t"

35
			"mov.l	@%7+, %3	\n\t"

36
			"mov.l	@%7+, %4	\n\t"

37
			"mov.l	@%7+, %5	\n\t"

38
			"mov.l	@%7+, %6	\n\t"

39
			"mov.l	@%7+, r7	\n\t"

40
			"mov.l	@%7+, r0	\n\t"

41
			"mov.l	%2, @(0x04,%0)	\n\t"

42
			"mov	#0x20, %2	\n\t"

43
			"mov.l	%3, @(0x08,%0)	\n\t"

44
			"sub	%2, %1		\n\t"

45
			"mov.l	%4, @(0x0c,%0)	\n\t"

46
			"cmp/hi	%1, %2		! T if 32 > count	\n\t"

47
			"mov.l	%5, @(0x10,%0)	\n\t"

48
			"mov.l	%6, @(0x14,%0)	\n\t"

49
			"mov.l	r7, @(0x18,%0)	\n\t"

50
			"mov.l	r0, @(0x1c,%0)	\n\t"

51
			"bf.s	1b		\n\t"

52
			" add	#0x20, %0	\n\t"

53
			: "=&r" (to), "=&r" (count),

54
			  "=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),

55
			  "=&r" (tmp5), "=&r" (tmp6), "=&r" (from)

56
			: "7"(from), "0" (to), "1" (count)

57
			: "r0", "r7", "t", "memory");

58
	}

59
#endif

60


61
	if ((((u32)to | (u32)from) & 0x3) == 0) {

62
		for (; count > 3; count -= 4) {

63
			*(u32 *)to = *(volatile u32 *)from;

64
			to += 4;

65
			from += 4;

66
		}

67
	}

68


69
	for (; count > 0; count--) {

70
		*(u8 *)to = *(volatile u8 *)from;

71
		to++;

72
		from++;

73
	}

74


75
	mb();

76
}

77
EXPORT_SYMBOL(memcpy_fromio);

78


79
/*

80
 * Copy data from "real" memory space to IO memory space.

81
 */

82
void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)

83
{

84
	if ((((u32)to | (u32)from) & 0x3) == 0) {

85
		for ( ; count > 3; count -= 4) {

86
			*(volatile u32 *)to = *(u32 *)from;

87
			to += 4;

88
			from += 4;

89
		}

90
	}

91


92
	for (; count > 0; count--) {

93
		*(volatile u8 *)to = *(u8 *)from;

94
		to++;

95
		from++;

96
	}

97


98
	mb();

99
}

100
EXPORT_SYMBOL(memcpy_toio);

101


102
/*

103
 * "memset" on IO memory space.

104
 * This needs to be optimized.

105
 */

106
void memset_io(volatile void __iomem *dst, int c, unsigned long count)

107
{

108
        while (count) {

109
                count--;

110
                writeb(c, dst);

111
                dst++;

112
        }

113
}

114
EXPORT_SYMBOL(memset_io);

115


116